Process eor



Patented Oct, 10, 1922.

m In

UNITEE) EATEN'H' OFFICE.

PROCESS FDR LINING- METAL TUBES, PIPES, AND THE LIKE.

N Drawing. Application filed December T 0 all whom it may concern:

Be it known that I, FERNANDO Alums, 'a citizen of the Republic of Brazil, residing at Schwanenwick 28, Hamburg, Germany, have invented a certain new and useful Process for Lining Metal Tubes, Pipes, and the like, for which I have filed applications Ger many Dec. 27, 1920, No. A, $4,620, and in Great Britain, Dec. 13, 1921, No. 33,515, and

of which the following is a specification.

This invention relates to a process for producing pipes, tubes and the like the interior of which are coated with a protective material. The process is carried out as follows The metal pipe or tube, which is manufactured by the use of centrifugal force, is rotated and liquid or half-set material. is then introduced into the interior of it, the mate rial being such that it has the property of hardening on drying and uniting with the rotating metal pipe.

The efiect of the centrifugal action is that the liquid or halfset material (for example cement or concrete) is forced against the rough interior of the metal pipe and becomes closely united therewith into a single Whole. The process depends upon the con- Serial No. 525,601.

dition that the interior of the pipe, made by centrifugal force, has a rough surface. If t e liquid or half-set material is pressed by centrifugal force against the inner surface whilst the liquid in the mass escapes an in destructible union between the inner and outer layer is formed. The outer layer can be made very thin and the 1s a pipe or tube which is resulting product particularly suitable for conducting liquids, for drainage purposes, or for carrying off any kind of chemical waste product, the pipe or tube benat uniform and ing reliably free from rust and having a smooth inner surface and tliANDG ARENS. 

